The Truth About Surgery to Prevent Breast Cancer

If you were diagnosed with cancer in one breast, would you consider having the other, healthy breast removed as a preventive measure? If so, you're not alone. A growing number of women with early-stage breast cancer are making the decision to have this type of surgery at the same time their cancerous breast is removed.

Many women are driven by fear and anxiety over developing cancer in the other breast, and they believe having both breasts removed will give them peace of mind. However, there’s no clear evidence this surgery, called contralateral prophylactic mastectomy (CPM), will improve their odds of survival. And the increasingly widespread use of CPM without documented benefit has many breast oncologists concerned.

A disturbing trend?

The percentage of women with one-sided, or unilateral, breast cancer undergoing CPM has jumped in recent years—from about 4 percent in 2002 to nearly 13 percent in 2012. Often, women make the decision to have both breasts removed without getting a firm recommendation from their surgeon, according to a report in March 2016 in JAMA Surgery.

Researchers surveyed 2,402 women (average age, 62) with newly diagnosed unilateral, early-stage breast cancer. They asked the women what factors went into their eventual decision to have CPM, breast-conserving surgery, or unilateral mastectomy, and which procedure their surgeon had recommended.

Overall, nearly 44 percent of the women said they’d considered CPM, and 17 percent underwent the procedure. Many of these women had no family history or gene mutation that put them at high risk of developing cancer in the other breast. And 38 percent of the women who considered CPM weren’t aware that the surgery would not improve their likelihood of survival.

Advice from their surgeon appeared to make a significant impact on the women’s decision. About 46 percent of the women said they didn’t get any advice about CPM from their surgeon. Nearly 21 percent of those who received no advice had the procedure. Compare that to the 37 percent of women whose surgeons advised them against having the procedure; only 2 percent went through with it.

Why remove both breasts?

A primary reason women say they undergo CPM is to reduce the risk of cancer from developing in their other breast, and by doing so, to improve their odds of survival. This incentive persists, despite studies showing that women of average breast cancer risk get little to no survival benefit from CPM.

Many women who opt to have CPM overestimate their risk of getting cancer in the healthy breast. The real odds are extremely low—only about 0.6 percent a year. Having additional treatments like chemotherapy, tamoxifen, or aromatase inhibitor drugs on top of unilateral surgery lowers the risk even further—to just 0.2 to 0.5 percent a year.

CPM might be worthwhile among women who carry an inherited BRCA1 or BRCA2 gene mutation. The risk of those women getting cancer in the second breast is high, between 10 and 25 percent. CPM appears to significantly improve survival in women with BRCA mutations.

Another potential advantage to CPM is that it prevents the need for future mammograms, magnetic resonance imaging (MRI), and other imaging tests to look for cancer in the remaining breast. Repeat screening involves time and expense, and for many women it’s extremely stressful.

A case for self-esteem

A breast cancer diagnosis is devastating. Understandably, the thought of losing one breast and living with an asymmetrical appearance for the rest of her life can add to a woman’s distress. That’s why some women choose CPM for cosmetic reasons.

Concern about appearance and the potential feelings of self-consciousness can be just as important as medical reasons when considering CPM. While new reconstructive surgery techniques can make the affected breast look almost identical to the other natural breast in some women, a symmetrical look can be difficult to achieve in thin, small-breasted women. Furthermore, women who’ve had CPM report high satisfaction with their appearance afterward.

CPM complications

Any surgery can have side effects and complications, some more so than others. CPM has about double the complication rate of a one-sided mastectomy, research finds. Many women choose to have breast reconstruction surgery after CPM. Complications from both CPM and reconstruction can include infection, bleeding, pain, tissue death, blood clots, and the need for a repeat surgery (such as to replace an implant).

Your odds of having a complication from surgery are higher if you have a condition like obesity, diabetes, heart disease, or pulmonary disorders.

CPM also results in permanent numbness in the chest wall and the nipple, if preserved. Some women who have the procedure complain afterward about body image issues, sexual dissatisfaction, and problems with implants.

Should you undergo CPM?

By some estimates, only about 10 percent of women with newly diagnosed breast cancer meet the criteria for CPM. The American Society of Breast Surgeons does not recommend that women at average risk with cancer in one breast undergo CPM.

Surgical oncologists recommend breast-conserving surgery and add-on treatments like chemotherapy or hormone therapy, because it is less invasive and has about the same survival rates as mastectomy.

If you’re at a higher risk for breast cancer, you may want to discuss having this surgery with your oncologist. According to the American Society of Breast Surgeons, you should consider CPM if you:

Carry the BRCA1 or BRCA2 gene.

Have a strong family history of breast cancer, but haven’t had genetic testing.

Had mantle radiation to the chest before age 30 (a type of radiation once used to treat Hodgkin’s lymphoma but rarely used today).

Your oncologist might also recommend CPM if you:

Carry another breast cancer risk gene, such as CHEK-2, PALB2, p53, or CDH1.

Have a strong family history of breast cancer, but don’t have the BRCA genes.

Want to avoid mammograms; for example, because you have dense breasts or you tend to miss screenings.

Want to improve the symmetry of your breasts during reconstructive surgery.

Are extremely anxious about your risk of getting cancer in the other breast (although therapy could be an easier way to overcome your anxiety).

Who shouldn’t have CPM?

This procedure isn’t recommended if you:

Have cancer in one breast, but you don’t have a gene mutation or strong family history.

You have BRCA-positive family members, but you test negative for the gene.

Have an aggressive form of breast cancer, such as inflammatory breast cancer or late-stage cancer.

Are at high risk for surgical complications because you’re obese, you have diabetes, or you smoke.

Making the decision

Ultimately, the decision to have CPM is up to you. Your concerns about your future health, body image, and other issues are personal. CPM could be the right choice if you’re concerned about your risk of a future breast cancer.

Before you make a decision, have a careful discussion with your oncologist about your breast cancer risks, and consider all your other treatment options.

Make sure you understand what’s involved in the CPM procedure, as well as its potential advantages and adverse effects. Find out whether a less invasive breast-conserving procedure might be just as effective. Finally, ask your surgeon to give you a clear recommendation based on your potential benefits and risks.

Breast cancer in men

It’s rare for men to get breast cancer. In fact, men make up less than 1 percent of all breast cancer cases. Among the small group of men who do get this cancer, an increasing number are choosing to have contralateral prophylactic mastectomy (CPM) to remove the healthy breast. Between 2004 and 2011, the percentage of men having prophylactic breast surgery nearly doubled—from 3 percent to almost 6 percent.

In men just as in women, there’s no evidence CPM improves survival, and it can increase the risk for complications. As a result, the American Society of Breast Surgeons doesn’t recommend CPM for men with breast cancer—even if they have BRCA gene mutations.

Stephanie Watson has written about consumer health for nearly two decades. Her work has been featured in such publications as WebMD Magazine, Healthline, Harvard Health Publications, and Arthritis Today.